Roller-blind for photographic cameras.



E. BRAUBURGEB.

ROLLER BLIND FOR PHOTOGRAPHIG CAMERAS.

APPLICATION FILED JAN. 28, 1907.

Patented Nov. 23, 1909.

, clutches having a certain amount of idle UNITED srArEs PATENT FFIQE.

ERNST BRAUBURGER, OF FRIEDENAU, NEAR BERLIN, GERMANY, ASSIGNOR TO THE FIRM OF OPTISCHE ANSTALT C. I. GOERZ AKTIENGESELLSCI-IAFT, 0F FRIEDENAU, I

NEAR BERLIN, GERMANY.

ROLLER-BLIND FOR PHOTOGRAPHIC CAMERAS.

Application filed January 28, 1907.

To all whom at may concern:

Be it known that I, ERNST BRAUBURGER, a citizen of the German Empire, and resident of Friedenau, near Berlin, Germany, have invented certain new and useful Improvements in and Relating to Roller-Blinds for Photographic Cameras, ofwhich the following is a specification.

My invention relates to improvements in roller-blinds for photographic cameras described in the specification of Letters Patent No. 833,916, the purpose of the invention being to provide means for stopping the movement of one or both curtains, without the use of toothed wheels or mechanism occupyinga considerable amount of space.

In the construction set forth in the prior specification referred to the movement of the curtains for the purpose of forming the aperture is stopped by abutments co-acting with the curtain-rollers. For this purpose the rollers are provided with pinions meshing with toothed wheels having abutments adapted to co-act with corresponding fixed abutments. This arrangement involves, as stated, the use of toothed gear and occupies a comparatively large amount of space if the curtains are of considerable length or the rollers are of small diameter. In the improved construction which will now be described these disadvantages are obviated by using clutches placed between a fixed abutment and a rolleraxle these clutches having a certain amount of free or idle movement. Preferably these clutches consist of concentric disks provided with abutments and adapted to be rotated relatively to each other until their abutments come into contact with each other. The amount of rotation which can be imparted to the roller before its movement is stopped,,de-' pends on the number of disks placed between the roller and the fixed abutment. The extent of the rotation can therefore be regulated by regulating the number of clutchdisks used. A similar arrangement of movement may be used for conveniently regulating the rotation of the roller which continues to move, in order to form the aperture,

when the first'roller has been stopped. This arran ement does'not interfere with the closing of the aperture after-the exposure so that during the rolling up of the curtains the aperture is closed. The clutch-disks for stop- ,Specification'of Letters Patent.

- up of the curtains.

- aperture.

Patented Nov. 23, 1909.

Serial No. 354,567.

ping the rotation of the two rollers are pref erably co-axial.

The invention is illustrated in the annexed drawing, in which Figure l is a front view of the curtains and winding mechanism part of the latter being shown in section. Figs.,2 and 8 are side-views of the clutches, showing the disks in their two end-positions. Fig. 4t is a sideview of the device by means of which the width of the aperture is regulated.

The curtains are marked a and Drespectively, 0 being the roller of the curtain a, and (Z (Z the rollers of the curtain Z). The spring-rollers actuating the two curtains are marked 6 and 7 respectively. As in theconconstruction illustrated in the specification of Letters Patent No. 833,916, the rollers (Z are co-akial with the roller 1% and are mounted loosely on the journals 9 of the latter. On the saidjournals g are placed friction-disks it, the inner surfaces of which bear against the said roller. The disks a have recesses is within which are placed clutch-rollers Z.

scribed with reference to the drawings are entirely analogous to corresponding elements of the construction described in the prior specification already referred to.

()n the journals g are mounted clutchdisks 171., each of which is provided with an abutment 71. These disks serve to limit the rotation of the rollers (1 during the rolling For this purpose each roller (5 is provided with an abutment o, and an abutment 7) is fixed to each side-wall of the casing. On the left-hand journal g there are arranged, in addition to the disks m, disks 9 provided with abutments 1.

s is thedisk for adjusting thewidth of the The abutment of the clutclrdisk adjacent this adjusting-disk projects into a hole with which the latter is provided, so that rotation of the adj Listing-disk causes the said clutch-disk to rotate.

A disk It fixed to the journal 9 is provided with an abutment u, and a box fixed to the adjusting disk .9 is provided with notches 1) adapted to be engaged by an abutment to fixed to the case for the purpose of adjusting the disk 8 in different ositions. A spring m allows of axially displacing the disk 8 for the purpose of altering its adjustment.

tation of the cu'rtainrollers continues until 7 the rollers d are stopped by means of the clutch-disks m, and the number ofdisks m provided is such that the train of abutments between the rollersd and the abutments p interrupts the rotation of the, said rollers at the n'ionient at which the curtain b has This further rotation of the axle 9 causes the roller to continue its rotation alone over"- been wound up as much as is required. Dur- "ing this part of the winding up operation the clutch-disks 1 are' also rotated, but the number of disks g is greater than the number of disks 9%, so that the disks g permit further rotation of the axle 9 after the r0 tation. of the rollers (Z has been stopped.

coming the friction between its surface and the siu'iiaces ol the rollers (l.

ot the roller continues until stopped. by the train of" disks g enacting with the adjusting,- disk 5 and the abutment a. The extent of this rotation, and the width of the aperture formed, depend on the adjustment of the dish a. \Vlien an exposure has been caused operating the lever y, the rollers t: (Z are rotated in the opposite direction, and rotate the clutch-disks m and gon the journals also in the direction opposed to that in which they were rotated for winding up. The curtains are thus after each exposure returned to their original positions.

lla i-ug now partimilarly described and as .c tion and. in what rznrer the same is to be performed, I declare that what I claim is:

1. In a photographic shutter tho combination with'two curtains adapted to be moved aswell independently each other as jointly and adapted to form a slit, of supporting rotatable rollers for said. curtains and means to take place hr adapted to successively interrup the move ment of the two curtains, said curtain movement controlling means comprising at least for one curtain rotatable clutch-members and an abutment, the clutch-members interposi- The rotation to each other and abutinents, each set of said aincd the nature of my said inven- ES T AVAILABLE COPY tioned between a curtain supporting-roller,

and said abutment and individually capable of idle rotation through certain angles.

2. In a photographic shutter the combination with two curtains adapted to be moved 3 as well independently of each other as jointly o and adapted to form a slit of supporting ro-' tatable rollers for said curtains, rotatable clutch-members and abutments, one set/of Y certain angles.

3. In a photographic shutter the combina- I tion with two curtains adapted to be moved as well independently of each other as jointly and adapted to form a slit of supportin rotatable rollers 'for said curtains, a set 0' coaxial rotatable clutch-members and an abutment, the clutch-members interpositioned between a curtain-supporting roller and said abutment and individually capable of idle rotation through certain angles.

4. In a photographic shutter the combination with two curtains adapted to be moved aswell independently of each other asjointly and adapted to form a slitlof supporting r0- tatable rollers for said curtains, two sets of rotatableclutch-members arranged co-axially clutch-members interpositioned between one of the two curtain-supporting rollers and an abutment and the clutch-members of the two sets individually capable of idle rotation through certain angles. v 5. In a photographic shutter the combination' withtwo curtains adapted to be moved; as well independently of each other as jointly and adapted to form a slit of supporting ro- Witnesses:

HENRY HASPER, WOLDEMAR HAUPT,

tatable'roll'ers for said curtains and means 

